1. Field of the Invention
The present invention is related to a sports boot that closes on top of the foot by means of transverse flaps that overlap partially, and is especially related to a boot, one of whose transverse flaps at least extends up to the top of the instep zone via a tongue oriented in the lengthwise direction of the boot.
2. Description of Background and Relevant Information
Sports boots of the aforementioned type are known, for example, by the boot styles "Formula 77", "Pro 77" and "Elite 77", marketed in 1977 under the brand name Tecnica, as well as by the disclosure of U.S. Pat. No. 4,974,346 and the published patent application EP 659 358. These boots comprise an upper that is used to retain the lower part of the leg, and a shell base for the retention of the foot. To this end, the shell base has a rear portion that encircles the ankle and that is shaped like an open tube that corresponds with the instep, and a front, split portion that surrounds the front of the foot and that is closed by transverse flaps. In addition, at least one of such flaps become extended into the instep zone by a relatively flexible tongue that extends in the lengthwise direction of the boot and is independent of the contiguous flank extending from the rear portion of the shell base that encircles the ankle. In a traditional manner, the upper of the boot is advantageously assembled so as to overlap the rear portion of the shell base that encircles the ankle, thus guaranteeing a certain imperviousness, and tightening and closure devices are associated to the upper and to the shell base.
By these various arrangements, the closure and tightening of these boots can be done differently between the upper and the shell base. Indeed, the tongue constitutes a junction element that is automatically adapted therebetween in the instep zone and thereabove, by virtue of its flexibility and its independence with respect to the contiguous flank of the rear portion of the shell base. Consequently, the tongue retains a certain flexibility in the area of the instep zone, notably to allow the bending of the upper when the boot is in the closed position. It also facilitates the passage of the foot when the boot is in the position for putting on and removing the boot since it encourages the upper to open like a tulip in the instep zone under the pressure exerted by the foot.
However, these boots equipped with instep tongues have disadvantages related to the lateral retention of the tongue in a constant overlapping position with respect to the contiguous flank of the rear portion of the shell base. Indeed, after a certain amount of use, the tongue tends to get separated naturally in the instep zone and, due to this fact, is capable of becoming wrongly positioned after the boot has been put on, and during the closure of the upper, and this then requires manual intervention.
This type of disadvantage is especially common in those cases where the tongue is simply separated by a slit or a vertical scallop from the contiguous flank of the rear portion of the shell base, as in the example of the boot disclosed by the patent application EP 659 358. In this example, the tongue is also devoid of any predetermined positioning direction since it does not even partially cover the flank of the shell base. Consequently, there is nothing to stop it from sliding above or beneath the contiguous flank of the shell base during the closure of the upper on the lower part of the leg, and thus from substantially modifying the way in which the wearer's ankle is enveloped, thereby adversely impacting comfort.
In the example of the boot according to U.S. Pat. No. 4,974,346, this disadvantage is avoided by virtue of providing other transverse flaps that originate from the contiguous flanks of the rear portion of the shell base that surrounds the ankle, and extend into the upper zone of the instep while being separated from the lower flaps via a transverse slit. More specifically, these upper flaps are positioned to overlap the instep tongues borne by the lower flaps, and they extend the inner wall of the contiguous flanks of the shell base up to the vicinity of the instep zone in a continuous manner. The result of this arrangement is that the tongues cannot become separated naturally from the instep zone and that their positioning with respect to the contiguous flanks of the shell base is almost immovable. However, the superposition of the tongues with the upper flaps coming from the contiguous flanks of the shell base has other disadvantages. As a matter of fact, in the overlapping area, it constitutes a stratified structure whose stiffness varies in accordance with the tension exerted by the tightening-closure devices of the upper, and this directly modifies the bending conditions of the upper with respect to the shell base. As such, the flexibility of the boot is not maintained in the instep zone. In addition, obtaining upper flaps in the rear portion of the shell base that encircles the ankle hinders the separation of the tongues, and thus the tulip-like opening of the upper in the instep zone during the putting on and removal of the boot. Finally, adding instep tongues, in the slit, on the lower flaps requires an assembly operation that adversely impacts manufacturing costs.
In the example of the boot-styles "Formula 77", "Pro 77" and "Elite 77", marketed in 1977 under the brand name Tecnica, the problem of keeping the instep tongue in a constant overlapping position is partially resolved by virtue of the oversizings of the tongue and of the contiguous flanks of the shell base that extend towards the front up to the vicinity of the instep zone.
More specifically, the tongue of the flap from which it originates is of such a size that it covers the two frontal edges of the flanks of the shell base in the instep zone, and it becomes inserted laterally on either side of the zone, up to a pint beneath the flaps of the upper of the boot. Due to these arrangements, the tongue is always placed on the outside of the contiguous flanks of the shell base but there is no guarantee that it can be maintained beneath the flaps of the upper. As a matter of fact, the action of putting on and removal of the boot requires the disengagement of the tongue from beneath the flaps of the upper, and this then puts it naturally into a position of covering these flaps. The solution implemented in these boots thus appears to be inadequate since it does not guarantee the constant maintenance of the tongue in a preferred overlapping position. Also, due to the over-sizing of the tongue and of the contiguous flanks of the shell base up to the vicinity of the instep zone, the passage of the foot becomes more difficult during the putting on and removal of the boot.